During trainings about Agile and Scrum I often use this image with the two triangles to compare two different mindsets with which projects can be approached; the Project Mindset and the Product Mindset.
The Project Mindset approach, in which success is defined upfront based on Scope, Time and Budget, will (based on experiences) lead to less business involvement and more task management.
The Product Mindset approach, in which success is continuously driven by business metrics like User adaption/retention, revenue cost saving per feature, will (based on experiences) lead to less waste, more creativity and more releases.
In the Project Mindset approach the focus is on delivering the whole scope (requirements) within time (deadlines) and budget (costs). This is an output driven process. But software development is not the same as an industrial assembly line, in which one is very close to knowing how to act (repeatable, predictable activities) and where there is a good agreement on what to build. Software development takes place in complex circumstances and is in itself a complex activity. Things change constantly; requirements change, technique changes and people change. That is why in the past this mindset has very often led to low quality of the product, because if time and money are running out, managers start to put pressure on the teams, teams will work harder and more sloppily, make more mistakes and/or even skip certain tasks (for instance certain ways of testing) to deliver faster.
In the Product Mindset approach the focus is on delivering high quality within a certain amount of time and costs (a Sprint has a fixed length, so fixed time and fixed costs). This is more an outcome driven process in which quality standards never decrease and work (Product Backlog) is ordered by Risc, CoO, ROI, other business value, etc. And if it seems that things turn out differently than planned, like time is running out, the scope is changed/reduced.
In the Product Mindset approach the goal is not to deliver all requirements, but to solve the problem, or fill in the original need of the business. And if that can be done without delivering all the requirements, then that will be done.
The Agile way of working is a Product Mindset approach.